Siemens Industry, Inc. MXG461…U, MXF461…U Series Technical Instructions Document No. CA1N4455E-P25 October 19, 2020 Modulating Control Valves with Magnetic Actuators MXG461…U MXF461…U Description Mixing or straight-through valves with magnetic actuators for modulating control of hot and chilled water systems in closed circuits. Features • Fast positioning time (< two seconds), high-resolution stroke (1:1000). • Linear or equal-percentage valve characteristic (user-selected). • Switch-selectable control signal: 0 to 10 Vdc, 2 to 10 Vdc, or 4 to 20 mA. • Wear-free inductive stroke measurement. • Low friction, robust, no maintenance required. • Fail-safe feature: A → AB closed when de-energized. • Positioning control. • Position feedback. • Manual control. Product Numbers See Table 1. Warning/Caution Notations WARNING: Personal injury or loss of life may occur if you do not follow the procedures as specified. CAUTION: Equipment damage or loss of data may occur if you do not follow the procedures as specified. Technical Instructions MXG461…U, MXF461…U Modulating Control Valves Document Number CA1N4455E-P25 with Magnetic Actuators October 19, 2020 Page 2 Siemens Industry, Inc. Application The MXG461...U (screwed fitting) and MXF461...U (flange fitting) valves are mixing or straight-through valves with a factory calibrated and mounted magnetic actuator. The magnetic actuator incorporates an electronics module for position control and positioning feedback. Control path A → AB is closed when the valve is de-energized. CAUTION: The valve is suitable for straight-through normally closed or three-way applications and may be installed only in a mixing arrangement. The direction of flow (A → AB) must be as indicated on the valve. The fast positioning time, high resolution and high rangeability make these valves ideal for modulating control of chilled and hot water systems in closed circuits. Sturdy construction makes maintenance and regular servicing unnecessary and ensures a long service life. Principles/ Construction Automatic Control The control signal is converted by the microprocessor in the electronics module into an output signal that generates a magnetic field in the core. This causes the only moving part, the armature, to change its position in accordance with the interacting forces (magnetic field, counter-spring, hydraulics, and so on). The armature responds rapidly to any change in signal, transferring the corresponding movement directly to the control disc, enabling fast changes in load to be corrected quickly and accurately. The valve position is measured continuously. The positioning controller ensures an exactly proportional relationship between the control signal and the valve stroke. Valve Characteristic Volumetric flow Control signal Volumetric flow Control signal Figure 1. Equal-percentage. Figure 2. Linear. Spring Return Function If the control signal is interrupted, there is a power failure, or if the power is switched off, the spring force closes the valve automatically (control path ports A → AB normally closed). MXG461…U, MXF461…U Modulating Control Valves Technical Instructions With Magnetic Actuators Document Number CA1N4455E-P25 October 19, 2020 Siemens Industry, Inc. Page 3 Manual Control The valve control path (ports A → AB) can be opened mechanically up to 90% of the full stroke by pressing the handwheel inward and turning it clockwise (to the MANUAL position). This disables the control signal from the controller, and the green LED will flash. To disable automatic control of the valve, press the handwheel inward and turn it counterclockwise (to the OFF position). The valve will close and the green LED will flash For automatic control, the handwheel must be set to the AUTO position. The handwheel will spring out and the green LED will be constantly lit. Figure 3. Selecting Automatic Control. Sizing Table 1. MX.461…U - Valves Sizing. Product Numbers Line Size C V P max Maximum Close-off Pressure S NA 1 P med 1 I N 1 Wire Gauge 18 16 14 12 (in) (gpm) (psi) (bar) (psi) (VA) (W) (A) Cable Length L (ft) MXG461.15-0.6U 1/2 0.7 44 3 44 29 5 3.15 108 213 361 525 MXG461.15-1.5U 1/2 1.7 44 3 44 29 5 3.15 108 213 361 525 MXG461.15-3.0U 1/2 3.5 44 3 44 29 5 3.15 108 213 361 525 MXG461.20-5.0U 3/4 5.8 44 3 44 29 5 3.15 108 213 361 525 MXG461.25-8.0U 1 9.3 44 3 44 29 5 3.15 108 213 361 525 MXG461.32-12U 1-1/4 14.0 44 3 44 29 5 3.15 108 213 361 525 MXG461.40-20U 1-1/2 23.0 44 3 44 44 6 4.00 66 118 197 328 MXG461.50-30U 2 35.0 44 3 44 44 6 4.00 66 118 197 328 MXF461.65-50U 2-1/2 58.0 44 3 44 46 6 5.00 49 98 164 262 Key: P max = Maximum permissible differential pressure across the valve’s control path, valid for the entire actuating range of the motorized valve. S NA = Nominal apparent power for selecting transformer P med = Typical power consumption I N = Required slow fuse C V = Flow rate to IEC534-2-4 Control path A → AB (normally closed): Tolerance ±5% Control path B → AB (normally open): Tolerance ±10% L = Maximum cable length. With four-wire connections, the maximum permissible length of the separate 16 AWG Cu (copper) signal cable is 656 feet. With three-wire connections, the maximum permissible cable length is reduced to 1/3 of the values shown in the table. 1 = All data relates to a 24 Vac supply. Technical Instructions MXG461…U, MXF461…U Modulating Control Valves Document Number CA1N4455E-P25 with Magnetic Actuators October 19, 2020 Page 4 Siemens Industry, Inc. Table 2. Water Flow Chart. Product Number Line Size (in) P V100 PSI C VS 1 2 3 4 5 6 7 8 9 10 15 20 30 40 50 MXG461.15-0.6U 1/2 0.7 0.7 1 1.2 1.4 1.6 1.7 1.9 2.0 2.1 2.2 2.7 3.1 3.8 4.4 4.9 MXG461.15-1.5U 1/2 1.7 1.7 2.4 2.9 3.4 3.8 4.2 4.5 4.8 5.1 5.4 6.6 7.6 9.3 10.8 12 MXG461.15-30U 1/2 3.5 3.5 4.9 6.1 7 7.8 8.6 9.3 9.9 10.5 11 14 16 19 22 25 MXG461.20-50U 3/4 5.8 5.8 8.2 10 12 13 14 15 16 17 18 22 26 32 37 — MXG461.25-8.0U 1 9.3 9.3 13 16 19 21 23 25 26 28 29 36 42 51 59 — MXG461.32-12U 1-1/4 14 14 20 24 28 31 34 37 40 42 44 54 63 77 89 — MXG461.40-20U 1-1/2 23 23 33 40 46 51 56 61 65 69 73 89 103 126 145 — MXG461.50-30U 2 35 35 49 61 70 78 86 93 99 105 111 136 157 192 221 — MXF461.65-50U 2-1/2 58 58 82 100 116 130 142 153 164 174 183 225 259 318 367 — LED Indicators The two-color LED display indicating operating status can be viewed by opening the cover of the electronics module. Table 3. LED Display. LED Display Status Description LED green On continuously Automatic mode: Auto (normal, no faults) Flashing – Mechanically set to MANUAL – Mechanically set to OFF – Currently in auto-calibration mode LED red On continuously – General fault – General calibration fault – Microcontroller fault Flashing – Faulty 24 Vac supply (that is, too low) LED Off – No 24 Vac supply – Fault with electronics module As a general rule, the LED can only assume the conditions in Table 3 (continuously red or green, flashing red or green, or off). Mounting Mounting and operating instructions are printed on the actuator and on the electronics module. The valve is suitable only for straight-through or three-way applications and may be installed only in a mixing arrangement. In the case of the straight-through valve, strict observance of the direction of flow is essential. Do not mount with actuator below horizontal position. Access for Mounting It is essential to maintain the specified minimum clearance above and to the side of the actuator and/or electronics module for servicing, installing and heat dissipation: • 1/2-inch to 1-1/4 inches = 4 inches • 1-1/2 inches to 2-1/2 inches = 6 inches Also see Dimensions. MXG461…U, MXF461…U Modulating Control Valves Technical Instructions With Magnetic Actuators Document Number CA1N4455E-P25 October 19, 2020 Siemens Industry, Inc. Page 5 Mounting, Continued Straight-through Valves Only three-way MXG461...U valves are supplied. They may be used as straight-through normally closed valves by closing off port "B": Port "B" can be sealed with the accessories supplied (blanking disk, gasket, and the nut). No blanking flange is available for MXF461.65-50U. Figure 4. MXG461...U Screwed Valves in Straight-through Applications. Installation MXG461...U screwed valves are flat-faced to facilitate sealing with the gaskets supplied. Do not use hemp, tape or thread-sealing compound. Do not insulate the actuator. For notes on electrical installation, see Terminal Layout. Maintenance The valves and actuators require no maintenance or service. The valve stem is sealed with a maintenance-free O-ring gland. Should the valve electronics prove faulty, the electronics module should be exchanged for a replacement part, part number ASE1 (1/2-inch to 1-1/4 inches) or ASE2 (1-1/2 inches to 2-1/2 inches). Mounting instructions are enclosed (Ref. 35678). After replacing the electronics module, calibration must be triggered to optimally match the electronics to the valve (see Calibration). WARNING: Under operating conditions within the limits defined by the application data, the actuator will become hot, but this does not represent a fire or burn risk. Always maintain the minimum clearance specified (see Dimensions). Technical Instructions MXG461…U, MXF461…U Modulating Control Valves Document Number CA1N4455E-P25 with Magnetic Actuators October 19, 2020 Page 6 Siemens Industry, Inc. Specifications Electrical Interface Power supply Class 2 Supply voltage 24 Vac, 50/60 Hz – Maximum voltage tolerance +20/–15% Control signal (user-selected) 0 to 10 Vdc, 2 to 10 Vdc, or 4 to 20 mA Software class Class A Nominal power See Sizing Position Signal Y 0 to 10 Vdc, 2 to 10 Vdc, or 4 to 20 mA Impedance 0 to 10 Vdc or 2 to 10 Vdc 100k Ω //5nF 4 to 20 mA 100 Ω //5nF Position feedback signal 0 to 10 Vdc; load resistance > 500 Ω Product Specific Data Applications To EN60730 Nominal pressure 232 psi (16 bar) Permissible Operating pressure p e max 150 psi Differential pressure P max See Table 1 Leakage at P v = 14.5 psi (0.1 Mpa) (1bar) A → AB Max. 0.02 % Cv (to IEC534-4) B → AB Depends on operating conditions (<0.2% C v ) Admissible media Water, or water/glycol mixtures with maximum 50% glycol Temperature of medium 34°F to 266°F (1°C to 130°C) Valve characteristic (stroke, k vs ) Linear or equal percentage (user- selected), optimized near the closing point (to IEC534-2-4) Stroke resolution H/H 100 1:1000 (H = stroke) Hysteresis Typically 3% Type of operation Modulating Manual adjustment Yes, with handwheel Position with actuator de-energized A → AB closed Orientation Upright to horizontal Note that orientation affects protection standard Positioning time <2 seconds Materials (valve body) Housing parts Cast iron Plug CrNi Steel Seat Brass Valve stem seal EPDM (O-ring) Bellows Tombac, bronze, CrNi steel Electrical connection Connection terminal Screw terminals Per terminal, with wire (no lug) 2 × 16 AWG or 1 × 14 AWG Per terminal with wire 2 × 16 AWG or 1 × 12 AWG Miscellaneous Weight (including packaging) See Dimensions Dimensions See Dimensions Ambient conditions Maximum ambient temperature 113°F (45°C) Agency Approvals UL listing Per UL 873 C-UL Certified to Canadian Standard C22.2 No. 24 Suitable for use in air handling spaces NEMA Type 1 MXG461…U, MXF461…U Modulating Control Valves Technical Instructions With Magnetic Actuators Document Number CA1N4455E-P25 October 19, 2020 Siemens Industry, Inc. Page 7 Wiring Terminals WARNING: Earth ground must be connected to the pipe work. 24 Vac 24 Vac Control signal input Control signal reference voltage 0 to 10 Vdc stroke signal output (position feedback) Override control Figure 5. Terminal Layout for Four-wire Connections. Wiring Diagram Figure 6. Connection to Controller with Four-wire Output. U = Indication of valve position (only where required). 0 to 10 Vdc → 0 to 100% volumetric flow. If the cables for the 24 Vac supply and the control signal 0 to 10 Vdc (2 to 10 Vdc, 4 to 20 mA are routed separately, twisted pairs are not required for the 24 Vac cable). Forced Control Feature (Input Terminal YF/6) 0 Vac (Bridge G0 – YF) 24 Vac (Bridge G – YF) 1 to 9 Vdc at F Control path A → AB closed Control path A → AB open Continuously variable low limit control 10% to 90% volume flow (the higher value YF of Y takes priority). This function is available with valves with a manufacturing date of 990701 or later. Technical Instructions MXG461…U, MXF461…U Modulating Control Valves Document Number CA1N4455E-P25 with Magnetic Actuators October 19, 2020 Page 8 Siemens Industry, Inc. Operator Controls and Indicators in the Electronics Housing Figure 7. Housing Components. 1 Connection terminals 2 Hand wheel 3 Opening for autocalibration 4 DIP switch for mode control 5. LED for indication of operating stat ok calib. / Man error error calib. green red 4461Z28 Configuration DIP Switches Switch Function ON/OFF Description Valve characteristic ON V . log (equal percentage) OFF V . lin (linear) 1) Positioning signal Y ON DC 2 to 10 V, DC 4 to 20 mA OFF DC 0 tp 10 V 1) [V] or [mA] ON [mA] OFF [V] 1) Valve characteristics ON ngl 3.0 OFF ngl 5.3 1) Assignment positioning signal Y: Voltage or current Selection of valve characteristic (Positioning signal against volumetric flow): Equal-percentage or linear MXG461…U, MXF461…U Modulating Control Valves Technical Instructions With Magnetic Actuators Document Number CA1N4455E-P25 October 19, 2020 Siemens Industry, Inc. Page 9 Calibration The MX…461…P magnetic valves are factory-calibrated at 0% and 100% stroke. When commissioning the valves (especially under extreme usage conditions) there may still be some leakage via control path A → AB with a 0% stroke control signal (0 Vdc, 4 mA or 2 Vdc). In this case, the valve can be recalibrated as follows (see Figure 8): • Use a pin or paper clip to push the button in opening (A) in the terminal housing. • During calibration, the LED light (B) in the electronics module will flash green for approximately 10 seconds. The valve will be briefly closed and fully opened. Application Example CAUTION: This valve is suitable for straight-through normally closed or three-way applications only and should only be installed in a mixing arrangement. A Mixing circuit B Mixing circuit with bypass (underfloor heating) C Injection circuit D Diverting circuit E Injection circuit with straight-through valve Figure 8. Hydraulic Circuits. Next >